Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2017 9 8.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/09/2017   22:27:58   (  -0.33,-135.09) (  -0.50,-135.89)   90.38                80
 09/10/2017   22:11:54   (  -0.33,-135.13) (   0.49,-131.35)  429.30                80
 09/12/2017   10:33:43   (   0.33,-135.20) (   0.67,-136.63)  163.72                80
 09/13/2017   10:12:20   (   0.33,-135.22) (  -0.37,-132.11)  354.62                80
 09/14/2017   22:34:17   (  -0.31,-135.21) (  -0.80,-137.42)  251.11                80
 09/15/2017   22:18:12   (  -0.32,-135.24) (   0.18,-132.88)  267.66                80
 09/17/2017   10:40:03   (   0.30,-135.31) (   0.92,-138.17)  325.19                80
 09/18/2017   10:18:38   (   0.31,-135.33) (  -0.07,-133.64)  192.77                80
 09/19/2017   22:40:36   (  -0.29,-135.30) (  -1.10,-138.94)  414.75                80
 09/20/2017   22:24:31   (  -0.30,-135.32) (  -0.11,-134.41)  103.85                80
 09/22/2017   10:46:20   (   0.28,-135.41) (   1.27,-139.69)  488.18                80